JPS6134921B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a tool element. This tool element carries cutting means and is detachably attached to the tip of the elongated holder body. Note that when the tool element carrying the cutting means and the elongated holder body are integrated, the whole becomes a cutting tool.

When machining workpieces on a lathe, tool holders are commonly used that include an elongated shaft, generally having a rectangular or round cross section. A cutting blade is attached to one end of the tool holder. The shaft is usually fastened to the lathe with two or three screws.

In machines using such known types of tool holders, when it is desired to change the type of cutting insert, the tool holder must be replaced by another holder, resulting in high handling costs. Besides, elongated shafts require a lot of space, which creates problems for machine designers. Furthermore, this technique is difficult to apply to mechanized tool replacement.

In order to try to overcome the above-mentioned problems, Swedish patent publication no. ing.

In this prior art design, the shaft on the tool element projects into a recess in the forward end of the drawbar. The shaft is provided with a cam surface on one side thereof adapted to cooperate with a complementary cam surface within the recess. During gripping of the tool element,
Relative movement along the cam surface causes the shaft to move laterally until it abuts a support surface in a recess opposite the cam surface. It has been found that due to the high cutting forces acting on the tool element during machining operations, this connection between the tool element and the holder body is not sufficiently rigid.

The object of the present invention is the Swedish Patent Publication No. 401469
The purpose of the present invention is to improve the cutting tool of the type shown in the No. 2003-2013 so that it has a satisfactory rigidity. The invention thus seeks to improve the accuracy of the positioning of the cutting implant.

Another object of the present invention is to provide a tool that can quickly and firmly grip not only right-handed but also left-handed tool elements within the same holder body.

A further object of the invention is to propose good possibilities for mechanization, so that a completely automatic mechanical change of tool elements can be achieved.

These and other objects of the invention are achieved by means of the characteristic advantages as set out in the appended claims.

In the following description, the tool elements of the invention will be explained in detail with reference to three exemplary embodiments, with reference to the accompanying drawings. It should be understood that these embodiments are merely illustrative of the invention and that various modifications of the invention may be made within the scope of the claims.

The cutting tool shown in Figs.
It includes a tool element 10 provided with cutting means in the form of a. The planar outer surface of the cutting insert 11 is arranged substantially in the same plane as the top surface of the tool element 10. The tool element 10 is an elongated shaft 1
2 at its outer end, the shaft 12 forming the main body of the tool holder.
The shaft 12 has a rectangular cross-section and is adapted to be securely mounted in a conventional manner on a lathe.

In the stopped position towards the front end of the holder body 12, the tool element body 10 is pressed against the support surface 13 and the support end face 14 perpendicular thereto on the holder body. The support end face 14 is cut out at a recess 15 which extends axially inwardly into the shaft 12. The axial support surface of tool element 10 thus consists of two surfaces 14a, 14b lying in the same transverse plane. The recess 15 is laterally bounded by opposing planar joint surfaces 16 and 17 extending parallel to each other in the longitudinal direction of the holder body 12. The recess 15 is intended to receive a correspondingly shaped shaft portion 18 on the tool element 10.

In order to stop the tool element 10, a longitudinally movable pull rod 19 is provided within the holder body 12. The front part 21 of the rod 19 is received in a correspondingly shaped groove 20 in the tool element 10.

In the embodiment depicted, the section 21 is designed as a cylindrically rounded enlargement and is connected to the main body of the shaft 12 over a narrowed cylindrical neck 22. The groove 20, which is designed in a restraining relationship with the rod 19, has a corresponding cylindrical shape, but has a slightly larger cross-sectional area than the enlarged portion 21.
The hole in the groove 20 is narrowed by projections 23, 24 which project into the groove from both sides thereof. Protrusion 2
3 and 24 define the axially inward facing end of the tool element 10, and have planar and mutually parallel side surfaces 2 on the outside.
5 and 26 are attached. In the parked position of the tool element 10, the side surfaces 25, 26 have recesses 15.
It is stationary toward the inner joint surfaces 16 and 17. The groove 20 ends on the underside of the tool element 10, while
Its upward extension is limited by the planar top surface of tool element 10. This design eliminates the problems caused by chip buildup within the joint. Such build-up will reduce the life of the joint and make it difficult to quickly disassemble it during tool element replacement.

When the tool element 10 is to be stopped against the holder body 12, the tool element 10 is first pushed towards it and rests with its bottom side towards the support surface 13 and also towards its rear end faces 14a, 14b. Do it like this. The enlarged portion 21 of the rod 19 is then received within the groove 20, while the shank portion 18 of the tool element 10 is received within the recess 15. Member 2 rotatably screwed to the rod
During tightening of the rod 19 by suitable operating means such as 7, the tool element 10 is pressed against the end faces 14a,b. When the rod 19 is further tightened, the protrusion 2
3 and 24 are made to extend in opposite directions in the lateral direction of the holder main body 12. The extension of the protrusions 23, 24 extends over the portion 21 adjacent to the neck 22 and on the protrusions 23, 2.
4 (see Figure 4). When the protrusions 23, 24 expand slightly, the latter are pressed against the joint surfaces 16, 17.
Thus, both sides 25 of the shank portion 18,
A high compressive force is applied on 26, thereby ensuring that the joint members have no play between them. In order to adapt the design of the tool element to its automated handling, the recess 15 for the tool element 10 is symmetrical with respect to a vertical plane passing through the axial centerline of the holder body 12. Thus, the tool element 10 can be mounted in the same holder body 12 in both left-handed and right-handed designs.

In the embodiment depicted, the enlarged portion 21 of the rod 19 is rounded into a cylindrical shape. however,
It should be understood that various modifications of this portion may be made. For example, the widened portion can be given a corresponding shape to the groove 20 as a dovetail.

6 and 7 show an alternative embodiment of the invention in which the shank portion 18 of the tool element 10 and the forward end of the holder body 12 are interconnected with a dovetail joint. Thus, the mouth of the recess 15 which receives the shank portion 18 is narrowed by mutually opposed wedge surfaces 28, 29 which are adapted to cooperate with complementary support surfaces on the shank portion 18. There is. The design of the pull rod 19 and the groove 20 receiving the enlarged portion 21 of the rod 19 is the same as that shown in FIGS. 1-5. However, instead, as mentioned above,
The connection between the drawbar 19 and the groove 20 can also be made as a dovetail joint.

8 and 9, a further embodiment according to the invention is shown having a modified connection between the holder body 12 and the tool element 10. Similar to the embodiment according to FIGS. 1 to 5, the side surfaces on the shank portion 18 of the tool element are planar and parallel to the joining surface 16 in the recess 15. However, the end 21 of the drawbar is in the form of a flattened cylindrical enlargement with two parallel, oppositely oriented planar surfaces 30,31. The distance between the surfaces 30, 31 corresponds to the diameter of the neck on the drawbar, which interconnects the widening 21 and the main body of the drawbar 19.

According to this embodiment, the drawbar 19 is not tightened until the tool element 10 is placed in its position, and then the drawbar is moved from the relaxed position shown in FIG. 8 to the restraint shown in FIG. rotated 90° into position. With such a design, the holder body 1
Insertion of the tool element 10 into the recess 15 in 2 is possible both straight from above and straight from the front. The latter insertion technique is desirable in mechanized replacement of tool elements.

[Brief explanation of the drawing]

FIG. 1 shows a side view of an embodiment according to the invention, in which the cutting tool is configured for right-hand rotation. 2 is a front view of the cutting tool of FIG. 1; FIG. FIG. 3 is a top view of the cutting tool of FIGS. 1 and 2; FIG. 4 is a bottom view of the cutting tool of FIGS. 1-3. FIG. 5 is a cross-sectional view taken along line A--A in FIG. 4. Figures 6 and 7 show side and top views, respectively, of an alternative embodiment of the invention. FIG. 8 is a top view of the front part of the holder body according to a further embodiment of the invention and a sectional view taken along B-B, with the tool element removed; There is. Figure 9 is the 8th
Figure 3 shows a top view and a cross-sectional view taken along line C--C of the holder body of the figure, with tool elements attached; Corresponding details in the various figures have been provided with the same reference numerals. Note that 10 is a tool element, 1
1 is a cutting element, 18 is a shank, 20 is a groove, 23
and 24 indicate protrusions.

Claims (1)

[Scope of Claims] 1. A tool element main body 10 having a cutting seat for accommodating a cutting blade 11, and this tool element main body having a contact surface that comes into contact with a corresponding surface 14 of a holder main body 12. Moreover, it is to be kept non-rotating with respect to the holder body 12 by means of a device provided on the holder body, furthermore said tool element body has an expandable shank 18 connected thereto, said expandable shank being connected to said holder body. A tool element adapted to be accommodated in a recess 15 of a body 12, wherein said tool element body 10 is reciprocably movable in a device 2.
1, said inflatable shank and reciprocatable device 21 including cooperating cam surfaces that allow said reciprocatable device to be accommodated in the cam surface of said inflatable shank 18. When the tool element body 10 is moved toward the holder body 12
Tool element, characterized in that said expandable shank is expanded so as to be drawn towards and lock said shank in a recess 15 of said holder body 12.